The long-range objective of the proposed research is to establish the function (or functions) of the pineal gland in birds. The immediate goals are to (1) better characterize the chemistry of this organ; (2) define the specific nature and role of the information that influences its chemistry, particularly that of melatonin and the enzymes associated with the formation of this unique molecule; and, (3) attempts to discover the identity of its products and their mode of release. The first goal, an understanding of the chemical dynamics of the pineal, has been the objective of several of our experiments in the last few years. These will be expanded in the proposed work. The second two goals will lead us into studies of the input-output functions of the pineal.